Li Jin-Qi, Li Jie, Wang Jia-Feng, Zhang Shu-Han, He Dan, Yong Rong-Sheng, She Shu-Ya
Sichuan Academy of Medical Science and Sichuan Provincial People's Hospital, Chengdu, 610072, China.
University of Electronic Science and Technology of China, School of Medicine, Chengdu, 610054, China.
Rapid Commun Mass Spectrom. 2018 Aug 30;32(16):1387-1395. doi: 10.1002/rcm.8174.
Fasiglifam is an orally available and selective partial agonist of hGPR40 receptor, which was unexpectedly terminated at phase III clinical trials due to its severe hepatotoxicity. To fully understand the mechanism of action of fasiglifam, it is necessary to investigate its in vitro and in vivo metabolic profiles.
For in vitro metabolism, fasiglifam was incubated with rat or human liver microsomes in the presence of β-nicotinamide adenine dinucleotide phosphate tetrasodium salt, glutathione (GSH) and uridine diphosphate glucuronic acid trisodium salt for 60 min. For in vivo metabolism, fasiglifam was orally administered to rats at a single dose of 20 mg/kg and the bile was collected. In vitro and in vivo samples were analyzed by the developed ultrahigh-performance liquid chromatography combined with Q-Exactive Orbitrap tandem mass spectrometry. The structures of metabolites were proposed according to their accurate masses and fragment ions.
A total of eight metabolites, including an acyl-GSH adduct, were detected and identified. M1 (acylglucuronide) and M5 (carboxylic acid derivative) were the major metabolites of fasiglifam. Metabolic pathways of fasiglifam involved oxygenation, oxidative dealkylation, dehydrogenation, glucuronidation and GSH conjugation. Fasiglifam may undergo metabolic bioactivation via acylglucuronide.
Oxidative dealkylation and glucuronidation were the predominant metabolic pathways of fasiglifam in vitro and in vivo. Metabolic bioactivation via acylglucuronide may be the perpetrator of its hepatotoxicity. Our findings would be helpful in understanding the disposition of fasiglifam as well as its hepatotoxicity.
法格列净是一种口服有效的人GPR40受体选择性部分激动剂，由于其严重的肝毒性，在III期临床试验中意外终止。为了全面了解法格列净的作用机制，有必要研究其体外和体内代谢谱。
对于体外代谢，将法格列净与大鼠或人肝微粒体在β-烟酰胺腺嘌呤二核苷酸磷酸四钠盐、谷胱甘肽（GSH）和尿苷二磷酸葡萄糖醛酸三钠盐存在下孵育60分钟。对于体内代谢，以20mg/kg的单剂量给大鼠口服法格列净并收集胆汁。通过开发的超高效液相色谱结合Q-Exactive Orbitrap串联质谱对体外和体内样品进行分析。根据代谢物的精确质量和碎片离子推测其结构。
共检测并鉴定出8种代谢物, 包括一种酰基谷胱甘肽加合物。M1（酰基葡萄糖醛酸）和M5（羧酸衍生物）是法格列净的主要代谢物。法格列净的代谢途径包括氧化、氧化脱烷基、脱氢、葡萄糖醛酸化和谷胱甘肽结合。法格列净可能通过酰基葡萄糖醛酸进行代谢生物活化。
氧化脱烷基和葡萄糖醛酸化是法格列净在体外和体内的主要代谢途径。通过酰基葡萄糖醛酸的代谢生物活化可能是其肝毒性的原因。我们的研究结果将有助于了解法格列净的处置及其肝毒性。
